Find And Replace

Hi All,

I have an 18 page document / brochure that I am working on.  I am trying to replace a certain colour on all objects with another colour.. I am putting in the relevant criteria i.e. CMYK colour, I hit find/replace...and a message says no objects found with that criteria.  This is rubbish, because there are!  I am using X8.  Can anyone advise?